I guess everyone who watches sageuk or taeha is more or less familiar with such words like seja, gongju, mama, jeonha. But in any case, a list of such terms may be useful.
Inside the palace complex, names were rarely used, and this is why those titles come in handy.
Here is the website of Royal Family in Korea (yes, the descendants are living): http://www.royalcity.or.kr/
The list was quite hard to find, but here it is, info taken from wikipedia:
King (wang, 왕, 王), the king, with the style of His Majesty (jeonha, 전하, 殿下) or, not as correct but yet still quite common, His Royal Highness (mama, 마마, 媽媽). Before the style of "jeonha" were used a variety of titles for the king. Native names such as "naratnim" (나랏님) and "imgeum" (임금) were also used colloquially. For references to late monarchs the title was Great Predecessor King (seondaewang, 선대왕, 先大王) or Great King (daewang, 대왕, 大王); for foreign envoys the title used was State King (gugwang, 국왕, 國王); and for those in the court who needed to mention the king outside his presence, and thus more formality was required in addressing the monarch, the title was Current King (geum-sang, 금상, 今上),Sovereign (jusang, 주상 , 主上 or sanggam, 상감 , 上監), or Grand Palace (daejeon, 대전, 大殿). The style remained the same for all titles with the exception of queens dowager and the relatively few kings who abdicated, who simply addressed or mentioned the king without using his style.
Queen consort (wangbi, 왕비, 王妃), the queen consort, with the style of Her Royal Highness (mama, 마마, 媽媽). The title used in the court language was Center Palace (junggungjeon, 중궁전, 中宮殿 or jungjeon, 중전 , 中殿). Queens consort that remained married to the king until their death were generally given a title consisting of two Hanja in the front and the customary suffix Queen (wanghu, 왕후, 王后) in the back.
King Former (sangwang, 상왕, 上王), a king who has voluntarily abdicated for his son to take his place. They usually remained influential or even powerful through the remaining years of their lives. The style of His Majesty (jeonha, 전하, 殿下) or, less frequently but yet still quite common, His Royal Highness (mama, 마마, 媽媽) was used.
Queen Dowager (daebi, 대비, 大妃), the current incumbent of the throne's mother, with the style of Her Royal Highness (mama, 마마, 媽媽). Queens dowager often exercised a great deal of influence on the king's influence through their regencies, which took place when the king was too young to rule in his own name, or simply through their role as the mother or even a senior female relative of the monarch.
Grand King Former (taesangwang, 태상왕, 太上王), an abdicated king whose relinquishment of power precedes that of another former king. The style of His Majesty (jeonha, 전하, 殿下) or, less frequently but yet still quite common, His Royal Highness (mama, 마마, 媽媽) was used.
Royal Queen Dowager (wangdaebi, 왕대비, 王大妃), a former consort preceding the least senior queen dowager or current king's aunt or grandmother, with the style of Her Royal Highness (mama, 마마, 媽媽).
Grand Royal Queen Dowager (daewangdaebi, 대왕대비, 大王大妃), a former consort senior to two other queend dowagers or the current king's great-grandmother, with the style of Her Royal Highness (mama, 마마, 媽媽).
Grand Internal Prince (daewongun, 대원군, 大院君), the father of a king who was unable to take the throne himself as he was not part of the generation following that of the last incumbent of the throne (kings who are honored at the royal Jongmyo Shrine must be senior generation-wise for the current incumbent to pay homage there). There have been cases when grand chief princes acted as regents for their sons, the last person to do so having been the Regent Heungseon.
Grand Internal Princess Consort (budaebuin, 부대부인, 府大夫人), the mother of a king whose father himself never reigned.
Internal Prince (buwongun, 부원군, 府院君), the queen consort's father.
Internal Princess Consort (bubuin, 부부인, 府夫人), the queen consort's mother.
Prince (gun, 군, 君), a son born to the match between the king and a concubine or a descendant of a grand prince. The style used is His Young Highness (agissi, 아기씨) before marriage and the style His Excellency (daegam, 대감, 大監) afterward.
Princess Consort (gunbuin, 군부인, 郡夫人), the consort of a prince.
Grand Prince (daegun, 대군, 大君), a prince born to the official match between the king and queen with the style of His Young Highness (agissi, 아기씨) before marriage and the style His Excellency (daegam, 대감, 大監) afterward. The title of a grand prince is not inherited and his sons are generally referred to as mere princes.
Grand Princess Consort (bubuin, 부부인, 府夫人), the consort of a grand prince.
Prince Royal (wonja, 원자, 元子), the firstborn son of the king before being formally invested as heir apparent, with the style of His Royal Highness (mama, 마마, 媽媽). Generally, princes royal were the son who was born first between the king and his official wife, but there were exceptions when the title of Prince Royal was given to the firstborn son of the king through a concubine, the most notable case having occurred in the reign of King Sukjong.
Royal Prince Successor (wangseja, 왕세자, 王世子) the heir apparent to the throne, with the eldest son of the king given precedence over his brothers given that there were no major problems with his conduct, with the simplified title Prince Successor (seja, 세자, 世子) being frequently used instead of the full name with the style of His Royal Highness (jeoha, 저하, 邸下). In less formal but still official court language, the title Eastern Palace (donggung, 동궁, 東宮) or Spring Palace (chungung, 춘궁, 春宮) and the style His Royal Highness (mama, 마마, 媽媽) was used intermittently with "Prince Successor," although the style was frequently dropped by more senior members of the royal family.
Royal Princess Successor Consort (wangsaejabin, 왕세자빈, 王世子嬪), the consort of the heir apparent, or simply Princess Successor Consort (saejabin, 세자빈, 世子嬪), with the style of Her Royal Consort Highness (manora, 마노라 or manura, 마누라). Later, as the distinction between "Her Royal Highness" and "Her Royal Consort Highness" became unclear due to the influence of the Andong Kim clan, the style Her Royal Highness (mama, 마마, 媽媽) also came to apply to the consort of the heir apparent. The style ~ Royal Highness also came to apply to grand princes, princes, and princess as well for the same reason.
Princess (gongju, 공주, 公主), the daughter of the official match between the king and his official wife, with the style of Her Young Highness (agissi, 아기씨) before marriage and Her Excellency (jaga, 자가) afterward.
Princess (ongju, 옹주, 翁主), the daughter of the king and one of his concubines, with the style of Her Young Highness (agissi, 아기씨) before marriage and Her Excellency (jaga, 자가) afterward.
Royal Prince Successor Brother (wangseje, 왕세제, 王世弟), the younger brother of the king who has been formally invested as heir presumptive as the king has no offspring.
Royal Prince Successor Descendant (wangseson, 왕세손, 王世孫), the son of the prince successor and the princess successor consort, and the grandson of the king, with the style of His Highness (hap-a, 합하, 閤下).
(Park Ji-Hwan/AFP/Getty Images)
Korean Tourism Org